Improve handling of very large length values during read/write

Author: flanglet

src/io/CompressedInputStream.cpp

@@ -427,11 +427,11 @@ int CompressedInputStream::_get(int inc)
 
 istream& CompressedInputStream::read(char* data, streamsize length)
 {
-    int remaining = int(length);
-
-    if (remaining < 0)
+    if (length < 0)
         throw ios_base::failure("Invalid buffer size");
 
+    streamsize remaining = length;
+
     _gcount = 0;
 
     while (remaining > 0) {
@@ -487,11 +487,11 @@ istream& CompressedInputStream::read(char* data, streamsize length)
 
         }
 
-        const int lenChunk = min(remaining, int(_available));
+        const streamsize lenChunk = min(remaining, streamsize(_available));
 
         if (lenChunk > 0) {
-            memcpy(&data[_gcount], &_buffers[_bufferId]->_array[_buffers[_bufferId]->_index], lenChunk);
-            _buffers[_bufferId]->_index += lenChunk;
+            memcpy(&data[_gcount], &_buffers[_bufferId]->_array[_buffers[_bufferId]->_index], size_t(lenChunk));
+            _buffers[_bufferId]->_index += int(lenChunk);
             _gcount += lenChunk;
             remaining -= lenChunk;
             _available -= lenChunk;

src/io/CompressedOutputStream.cpp

@@ -361,18 +361,18 @@ bool CompressedOutputStream::removeListener(Listener<Event>& bl)
 
 ostream& CompressedOutputStream::write(const char* data, streamsize length)
 {
-    int off = 0;
-    int remaining = int(length);
-
-    if (remaining < 0)
+    if (length < 0)
        throw IOException("Invalid buffer size");
 
+    streamsize off = 0;
+    streamsize remaining = length;
+
     while (remaining > 0) {
-        const int lenChunk = min(remaining, _bufferThreshold - _buffers[_bufferId]->_index);
+        const streamsize lenChunk = min(remaining, streamsize(_bufferThreshold - _buffers[_bufferId]->_index));
 
         if (lenChunk > 0) {
-            memcpy(&_buffers[_bufferId]->_array[_buffers[_bufferId]->_index], &data[off], lenChunk);
-            _buffers[_bufferId]->_index += lenChunk;
+            memcpy(&_buffers[_bufferId]->_array[_buffers[_bufferId]->_index], &data[off], size_t(lenChunk));
+            _buffers[_bufferId]->_index += int(lenChunk);
             off += lenChunk;
             remaining -= lenChunk;
 

src/test/TestCompressedStream.cpp

@@ -16,6 +16,7 @@ limitations under the License.
 #include <cstdio>
 #include <fstream>
 #include <iostream>
+#include <limits>
 #include "../io/CompressedInputStream.hpp"
 #include "../io/CompressedOutputStream.hpp"
 #include "../io/IOException.hpp"
@@ -202,6 +203,43 @@ uint64 compress5(kanzi::byte block[], uint length)
     return res;
 }
 
+uint64 compress6(kanzi::byte block[])
+{
+    CompressedOutputStream* cos = nullptr;
+    CompressedInputStream* cis = nullptr;
+    uint64 res;
+
+    try {
+        cout << "Test - large read request does not overflow streamsize" << endl;
+        stringbuf buffer;
+        iostream ios(&buffer);
+        cos = new CompressedOutputStream(ios, 1, "HUFFMAN", "TEXT");
+        cos->write((const char*)block, 1);
+        cos->close();
+        ios.seekg(0);
+        cis = new CompressedInputStream(ios, 1);
+        char decoded[1] = { 0 };
+        const streamsize requested = streamsize(numeric_limits<int>::max()) + streamsize(1);
+        cis->read(decoded, requested);
+
+        if ((cis->gcount() != 1) || (decoded[0] != char(block[0]))) {
+            cout << "Failure: invalid read result for large request" << endl;
+            res = 1;
+        }
+        else {
+            res = 0;
+        }
+    }
+    catch (const ios_base::failure& e) {
+        cout << "Failure: unexpected exception " << e.what() << endl;
+        res = 1;
+    }
+
+    delete cos;
+    delete cis;
+    return res;
+}
+
 int testCorrectness(int, const char*[])
 {
     // Test correctness
@@ -240,6 +278,9 @@ int testCorrectness(int, const char*[])
             cres = compress5(values, length);
             cout << ((cres == 0) ? "Success" : "Failure") << endl;
             res &= (cres == 0);
+            cres = compress6(values);
+            cout << ((cres == 0) ? "Success" : "Failure") << endl;
+            res &= (cres == 0);
         }
     }